The scutum is the largest sclerite of the mesonotum. In Tephritidae most of the thorax visible in dorsal view is the scutum (the only other parts directly visible in dorsal view are the postpronotal lobes, notopleura, scutellum, and occasionally the postnotum). The scutum is more or less rectangular and includes pre- and postsutural areas incompletely divided by the transverse suture. In Tephritidae it often has clear areas in the cuticle called xanthines. Their color may appear white or yellow, depending upon the underlying tissues and the state of preservation of the specimen. In Anastrepha and Toxotrypana, these areas may be difficult to distinguish, especially in dried specimens of predominantly yellow or orange species in which they are less contrasting. Dorsally these areas usually include the postpronotal lobe, most of the scutellum, and a number of vittae (stripes). Frequently there is an unpaired medial vitta on the scutum extending from near the anterior margin almost to the posterior margin. It usually broadens posteriorly in various shapes.